New azo-dyestuffs



United States Patent NEW AZO-DYESTUFFS Walter Hanhart, Riehen, Switzerland, assignor to Ciba 5 Limited, Basel, Switzerland, a Swiss firm No Drawing. Application October 11, 1954, Serial No. 461,681

Claims priority, application Switzerland October 23, 1953 12 Claims. or. 260-157) This invention provides valuable new azo-dyestuffs of 15 the formula in which R1 represents the radical of a hydroxybenzene. ortho-carboxylic acid or a heterocyclic radical having a S-membered hetero-ring which contains at least two hetero-atoms of which at least one is an exclusively cyclically bound nitrogen atom, and R3 represents a radical which contains a total of three benzene nuclei of which the end benzene nucleus is substituted by a hydroxyl group and a carboxylic acid group in ortho-position to the hydroxyl group and two of the three aforesaid benzene nuclei are bound together by an azo linkage, and in which the sulfonic acid group is bound to a fl-carbonatom of the 6-membered ring I.

The invention also provides a process for making the azo-dyestuffs of the above general Formula 1, wherein a 0 complex copper compound of such azo-dyestufl is decoppered. a

The copper compounds used as starting materials for the process are obtained by treating an azo-dyestuff of the general formula SOsH n in which R1 represents the radical of a hydroxybenzeneortho-carboxylic acid or a heterocyclic radical containing a S-membered hetero-ring which contains at least two hetero-atoms of which at least one is an exclusively cyclically bound nitrogen atom, and n represents a whole number not greater than 2, and in which the sulfonic acid group is bound to a fl-carbon atom of the 6-membered ring I in an alkaline medium with a compound of the general formula HOaS NH;

in which Ra represents a radical containing a total of three benzene nuclei of which the end benzene nucleus is substituted by a hydroxyl group and a carboxylic acid group in ortho-position to the hydroxyl group, and two of the three aforesaid benzene nuclei are connected together by an azo linkage.

The amino-monoazo-dyestuifs of the Formula 3 can I be made by coupling a diazo-compound of an amine of the formula R1NH2 with a 1-amino- 2-methoxyor ethoxy-naphthalene-6- or 7-sulfonic acid. As amines of the formula Ri-NH: there come into consideration, for example, amino-hydroxybenzene carboxylic acids of which the hydroxyl and carboxylic acid groups are in ortho-position relative to one another, such as 4-aminol-hydroxybenzene-2-carboxylic acid.

With advantage there may be used amines of the formula R1-NH2 which contain a hetero-ring of the kind defined above. The NHa group may be bound directly to this ring, but it may be bound to an aromatic ring, for example, to a benzene ring, which is either linked to the aforesaid hetero-ring by a simple direct bond or is fused thereto (that is to say, in the latter case two ring carbon atoms of the aromatic ring also form part of the heteroring). The hetero-ring contains at least two heteroatoms, of which at least one is an exclusively cyclically bound nitrogen atom, that is to say, a nitrogen atom of which all three valences are taken up in ring formation.

The production of the dyestuffs of the present invention is facilitated by starting from initial components which are free from hydroxyl groups which impart a capacity for coupling to the component.

Valuable results are obtained, for example, with diazocompounds of the formula R1-NH2 in which the amino group is bound to a benzene ring of which two vicinal ring carbon atoms also form part of a S-membered hetero-ring containing at least two nitrogen atoms, at least one of the said nitrogen atoms being an exclusively cyclically bound nitrogen atom.

As examples of suitable initial components there may be mentioned the following compounds:

tt-amlno -indazole' OH NH:

amino-mums G-amiuobenzimidazole 2-methy1-G-amino-henzimidazole 'I-aminobenzlmldazole 4- or 7-aminobenztriazo1e 6.-amiuobenztriazole G-aminobenzthiazole and also compounds of the formulae 'SOaH (subsequently sulfonated, but g-ppsttipn of the sulfonic acid group is uncertain) HOOO--C-N\ (IF-NH:

The starting materials of the Formula 4 are made by coupling Z-amino-5-hydroxynaphthalene-7-sulfonic acid in an acid medium with a diazo-compound of the formula R3X, in which X represents a diazotizable amino group. The radical Rs contains a total of three benzene nuclei and the end benzene nucleus, that is to say, the benzene nucleus furthest from the diazotized -NH2 group, is substituted by a hydroxyl group and a carboxylic acid group in ortho-position to the hy droxyl group. Two of the three benzene nuclei, for example, the two end benzene nuclei are connected together by an azo linkage. The third benzene nucleus may be connected, for example, by a bridge member u h a a 0--.NH-- g p .or a direct boud- Apa from the substituents already mentioned, the benzene nuclei of the radical R3 may contain further substituents, for example, halogenatoms such as chlorine, or alkyl or alkoxy groups of low molecular weight. It is generally of advantage for the diazotized NH2 group, the bonds between the several benzene nuclei and the hydroxyl group of the vend benzene nucleus all to be in para-position relatively to one another.

Valuable results are obtained, for example, with diazo compounds of the constitution in which ,X represents a diazotized amino group, R4;represents adiphenyl radical bound in the 4- and 4-positions tothe group X and the azo linkage, and R5 represents the radical of a hydroxybenzene ortho-carboxylic acid bound to the azo linkage inpara-position relatively to the hydroxyl group. Such compounds can be made in known manner by coupling on one side a tetrazotized 4:4'-diaminodiphenyl such, for example, as 3:3'-dimethyl-, 3 :3 '-dichl oro-, 3 :3 '-dimethoxy-4 4'-diaminodiphenyl or 4:4'-diam inodiphenyl itself with a hydroxybenzene orthocarboxylic acid capable of coupling. As such coupling components there come into consideration, 5- or 6- methyl-l-hydroxybenzene-Z-carboxylic acid, 6-chloro-lhydroxybenzene Z-carboxylic acid and especially l-hydroxybenzene-Z-carboxylic acid.

The diazo compounds of the amino-azo-dyestufis, which corresponds to the Formula 3, are coupled with compounds of the Formula 4 in an alkaline medium for example a medium rendered alkaline with an alkali carbonate, if desired with the addition of a suitable agent assisting the coupling, such as alcohol of pyridine.

The resulting dyestuffs of the Formula 2 are then treated With an agent yielding copper under conditions such that the group CnH2n+1 is split off with the formation of the orthozortho'-dihydroxy-azo-copper complex and oxidation occurs to form the triazole ring. As agents yielding copper there come into consideration more especially the copper tetrammine complexes obtainable in known manner from copper salts and ammonia or organic bases such as pyridine or ethanolamines. In order that the treatment with the agent yielding copper shall lead to the formation of the orth0:ortho'-dihydroxy-azo-copper complex with the splitting mi of the methylorethylgroup and also oxidation .to form the-triazole ring, energetic reaction conditions are usually necessary, that is to say, prolonged reaction at a raised temperature, for example, in the vicinity of the boiling temperature of the aqueous reaction medium, and also a substantially largerproportion of the agent yielding copper than one atomic proportion of copper per molecular proportion of dyestuff. Good results are obtained, for example, with about 4 atomic proportions of copper per 1 molecular proportion of dyestutf, whereby, in addition to the reactions mentioned above, the formation of a complex occurs also at the end ortho-hydroxy-carboxylic acid groups .or at the heterocyclic rings which may be.

present in the radical R1.

By the treatment with an agent yielding copper there is obtained a complex copper compound of a dyestufi of the Formula 1. The resulting copper compound is then decoppered. The decoppering may be carried out- OCH:

dilute hydrochloric acid at a raised temperature or by means of an alkaline solution of an alkali cyanide. The dyestuffs resulting from decoppering in an acid medium are advantageously reconverted into their sodium salts by means .of an alkali.

The copper-free dyestuifs corresponding to the above Formula 1 are suitable for dyeing and printing a very wide variety of materials, for example, those of animal origin such as wool, silk or leather but especially for dyeing or printing cellulose-containing materials such as cotton, linen, and artificial silk or staple fibers of regenerated cellulose. They may also be treated with an agent yielding metal, advantageously an agent yielding copper, on the fiber or in the dyebath. For this purpose there are especially suitable those dyestuifs which contain no sulfonic acid groups other than those shown in the formula. The treatment with the agent yielding metal may be carried out in known manner, for example, on the fiber or in a single bath in part in the dyebath itself and in part on the fiber. It is of advantage to use the process, for example of U. S. Patent No. 2,148,659 in which there are carried out in the same bath first the dyeing and then the treatment with'the agent yielding metal. As agents yielding metal there come into consideration more especially those which are stable towards alkaline solutions, such as complex copper tartrates or alkali copper pyrophosphates.

In some cases especially valuable dyeings can be produced by the process in which a dyeing or print produced with the metal-free dyestulf is after treated with an aqueous solution which contains a basic formaldehyde condensation product of a compound containing at least once the atomic grouping.

. a1 -N=Q N for example, dicyandiamide or dicyandiamidine, or a compound, for example, cyanamide, which can easily be converted into a compound containing the aforesaid atomic grouping, and which solution also contains a waterasoluble, more especially a complex, copper compounds .Such a. process. is' described, for example, m BritishsPatent No. 619,969.

:6 The dyeings produced with the new dyestuffs in the manner described above are generally distinguished by their good properties of fastness, especially by their good fastness to light and washing.

The following examples illustrate the invention, the parts being by weight unless otherwise stated.

Example 1 10.6 parts of the sodium salt of the azo-dyestutr" of the formula (obtained by coupling diazotized 6-aminobenztriazole with l amino 2 methoxy naphthalene 6 sulfonic acid followed by diazotization of the monoazo-dyestuifand coupling with the disazo-dyestuif obtained by coupling tetrazotized 4z4' diaminodiphenyl on the one hand in an alkaline medium with 2-hydroXybenZene-1-carboxylic acid and, on the other, in an acid medium with 2 amino 5 hydroxynaphthalene 7 sulfonic acid) are stirred in 200 parts of water and the mixture is heated to 95 C. There is then added an ammoniacal solution of copper oxide prepared from 10 parts of crystalline water, filtered, andthefilter residue is washed with water or a dilute solution of sodium chloride. After converting the dyestuff in the usual manner into its sodium salt and drying it, the dyestufi is a green-black powder which dissolves in concentrated sulfuric acid with a red-brown coloration and in water with an olive-green coloration. It produces on vegetable fibers by the single bath or Z-bath after-coppering process olive-green tints which are fast to washing and light.

The decoppering may also be carried out with dilute hydrochloric acid at a raised temperature or by treatment with an alkaline solution of sodium cyanide.

In the following table are given further trisazo-dyestutfs obtainable .in the manner described above. Thus, the diazo-azo compounds given in column III are coupled in an acid medium with 2-amino-5-hydroxynaphthalcne-7- sulfonic acid, and the resulting disazo-dyestulfs are coupled in an alkaline medium with the diazo compounds of the aminomono-dyestuffs obtained from the initial components given'in column I and the middle components given in column II, the tetrakisazo-dyestufis are then converted in the manner described into the orthozortho dihydroxy-azo-copper complexes with the simultaneous oxidation of the ortho-amino-azo-grouping to the triazole ring, and the copper is finally removed. The dyestufis so obtained yield by the single bath or two-bath aftercoppering process on cellulose-containing fibers fast oliven am r Diem-compound (to be coupled with the dlsazo-dye'stufl obtained according to column III) of thetimluomonoazo-dyestufi from Diazo azo-compound to becoupled in acid medium with Z-amino--hydroxynaphthalenaJ-sulfonlc acid 7 Initial component Middle component I II III 5-amino-indazole 1-amino-2-methoxynaphthalene-6-sultetrazotlzcd 4i4-diaminodiphenyl, coupled on one-side with ionic acid. l-hydroxybenzene-Z-carboxyllo acid. G-amino-indazole ,Do. 7-a1nino-indazole Do. 5-aminobenzimidazole D0. 2-methyl-6-aminobenzimldazole. Do. 7-amino-b enzimidazole Do. 6-arnino-benzthlazole D0.

HN--GOH; Do.

9 HOOC-0-N when Do.

O-NH;

10 o-aminobenztrlazole 1-;un;no-fiethoxynaphthalene-6-sul- Do.

on c ac 1-amino-2-methoxynaphthalene-ti sultetrazotized 4:4-diaminodiphenyl. eoupledon oneslde with ionic acid. fi-chloro-l-hydroxybenzene-2-carboxylie acid. l -do. tetrazotized 4:4-diaminodiphenyl, coupled on one side with 6Inethy1-l-hydroxybenzene-2-carboxyllc acid. 13 "do do tetrazotized 3:3 -dimethoxy-4:4-diami.no-diphenyl, coupled on one side with l-hydroxybenzene-Z-carboxylic acid. 14 .do do tetrazotized 1-amino-4-(4-aminobenzoylami11o)-benzene, coppled on one side with l-hydroxy-benzene-2-oarboxyllc ac 15 ..do ..do t. diam-compound oi the amlnoazo-dyestufi of the formula: -HzN-C N=NO-C O-HN -OH JJOOH Example 2 perature of the dyebath is raised to 90-95 C. in the 10.8 parts of the sodium salt ofthe' tetrakisazo dyestufi course of minutes, 40 Parts of crystalline Sodium $111 of the formula fate are added, and dyeing is carried on for minutes H00 0 (|)CH3 HO HOaS NH: COOH obtainable in known manner are heated in 200 parts of at 90-100" C., then the bath is allowed to cool to about water and 200 parts of pyridine to about 95 C. There 70 C., and 3 parts of complex sodium copper tartrate is then added an ammoniacal solution of copper oxide of approximately neutral reaction are added, coppering prepared from 10 parts of crystalline copper sulfate, is carried on at about .80" C. for about A: hour, and parts of water and 25 parts of a'solution of ammonia of then the y g is finsfld with cold Walef- If desired, 24 percent strength, and the whole is stirred for about the y g may be soaped by after-treatment with a 6 hou t -95 c, Af goofing the mixm it i solution which contains 5 parts of soap and 2 parts of diluted with water, and the precipitatedudyestuff is anhydrous Sodium Carbonate 1000 Parts of Waterfiltered off and de-metallized by stirring :it for 3 hours in Th r s obtained a olive green dyeing of good fastness cold hydrochloric acid of 30 percent strength. The Washing and lightmixture is then diluted with water, filtered; andthe What I Claim is;

filter residue is washed with water. The dyestuff iscon- A11 azo-dyestufi 0f the formula verted into its sodium salt in the usual manner and dried. OH HO There is obtained a greenish black powder which dissolves in concentrated sulfuric acid with a red-brown R1 N=N coloration and in Water with an olive green coloration.

The coppered dyeings' on cotton are olive green and a o fast to washing and light.

parts'of cotton are entered at 50 Qinto a dyebathin whichRrrepresents a member selected from the group which. contains .4000 parts tofi water, 1.5 parts :of the consisting of the radical .of a hydroXybenzene-ortho-.

dccoppercd dyestuif obtained as described in Example and 2 parts of anhydrous sodium carbonate. The tem- 'carboxylic acid, an indazole radical, a ibenzimidazolc radical, a benzthiazolc radical and a benztriazole radical,

anew:

and R: represents a radical containing a total of 3 benzene nuclei of which the end benzene nucleus is substituted by a hydroxyl group and a carboxylic acid group bound in ortho position to the hydroxyl group two of the three benzene nuclei being bound together by an azo linkage, and in which dyestulf the sulfonic acid group is bound to a p-carbon atom of the six-membered ring I.

2. An azo-dyestuff of the formula OH HO R1N=N- N=N sotu Nr r-arin which R1 represents a benztriazole radical, and R3 represents a radical containing a total of 3 benzene nuclei of which the end benzene nucleus is substituted by a hydroxyl group and a carboxylic acid group bound in ortho position to the hydroxyl group two of the three benzene nuclei being bound together by an azo linkage, and in which dyestuif the sulfonic acid group is bound to a B-carbon atom of the six-membered ring I.

4. An azo-dyestuff of the formula Iii-N=N N=N- I HOsS- N in which R1 represents a benzimidazole radical, and Rs H000 OH HO N=N Ross represents a radical containing a total of 3-5 benzene nuclei of which the end benzene nucleus is substituted by a hydroxyl group and a carboxylic acid group/bound in ortho position to the hydroxyl group two of the three benzene nuclei being bound together byan azo linkage, and in which dyestufi the sulfonic acid group is bound to a B-carbon atom of the 'six-membered ring I.

5. An azo-dyestufi of the formula HOrB N-NRrN=N-R| in which R1 represents a radical of a hydroxybenzeneortho-carboxylic acid, R4 represents a diphenyl radical bound in the 4- and 4'-positions to the triazole ring and the azo linkage, and R5 represents the radical of a hydroxybenzene-ortho-carboxylic acid bound to the azo linkage in para-position to the hydroxyl group.

6. An azo-dyestufi of the :fromula in which R1 represents a benztriazole radical, R4 represents a diphenyl'radical bound in the 4- and 4-position to the triazole ring and the azo linkage, and R5 represents the radical of a hydroxybenzene-ortho-carboxylic acid bound to the azo linkage in para-position to the hydroxyl group.

7. An azo-dyestuff of the formula Fri-N=N N=N HOaS in which R1 represents a benzimidazole radical, R4 represents a diphenyl radical bound in the 4- and 4-positions to the triazole ring and the azo linkage, and R5 represents the radical of a hydroxybenzene-ortho-carboxylic acid bound to the azo linkage in para-position to the hydroxyl group.

8. The azo-dyestulf of the formula COOH 9. The azo-dyestufi of the formula N COOH NLL MGOH "11 -10."The azo-dyestuff of the formula References Cited infzhe file of vthis patent UNITED STATES PATENTS 2,268,935 Hanhart Jan. 6, 1 942 

1. AN AZO-DYESTUFF OF THE FORMULA 